Lock for doors and the like



Jan. 26, 1954 v H. THORNE LOCK FOR DOORS AND THE LIKE s Sheet s-Sheet 1 Filed Aug. 17, 1949 hike/1hr HRRQL'D Fianna 'H. THORNE LOCK FOR DOORS AND THE LIKE Jan. 26, 1954 3 Sheets-Sheet 2 Filed Aug. 17. 1949 //)ve/7/Zr HHQoLp THOENE Jan. 26, 1954 H. THORNE LOCK FOR DOORS AND THE LIKE 3 Sheets-Sheet 5 Filed Aug. 17. 1949 In yen for HHEOLD THORHE Patented Jan. 26, 1954 UNITED STATES PATENT OFFICE LOOK FOR DOORS AND THE LIKE Harold Thome, London, England Application August 17, 1949, Serial No. 110,769

2 Claims.

This invention relates to locks for doors and the like and has more especial reference to latches having double throw bolts in which a spring urged bolt is adapted, on the door being opened by the handle or key, to take up an intermediate position, and on the door being closed to be shot by its spring to a full stroke position securely within the keeper.

The present invention has for its object to provide an improved, readily constructed, durable and eflicient latch arrangement of this character which effectively removes the likelihood of unauthorised opening of the door or the like except by the appropriate key or by turning the conventional inside knob where provided.

With such an arrangement the bolt of a latch can be made to protrude only a rounded nose portion like an ordinary latch bolt when the door is open and to shoot home into a deep keeper when the door is closed, the bolt moving from one position to the other due to depression of the bolt against a striking plate as the door closes.

In the improved latch type lock for doors and t the like according to the present invention, a

cam track is associated with the spring urged bolt and in this cam track rides a detent which is caused to move unidirectionallyround the track to alternatively and successively limit the travel of the bolt to its full stroke and intermediate positions respectively.

In one construction the detent consists of a spring urged lever which has a tail entered in a recess in the bolt, the recess having a labyrinth track through which the lever tail can pass only in one circulating direction so that on repeated depressions of the bolt the lever tail moves alternately between a bolt-held position and a bolt-free position. In the bolt-held position the lever tail occupies a U-shaped notch open towards the nose of the bolt and due to its spring and a deflector at the mouth of the notch, the lever tail can leave the notch only at one side and enter it at the other after having passed a spring non-return gate at the end of the recess remote from the nose of the bolt. The same spring can serve to shoot the bolt and control the detent lever.

The handle of the latch bolt may be carried on the bolt by a spring-urged or drop lever having an abutment to enter a notch in the latch case when the bolt is shot so that thebolt cannot be retracted except by means ofthehandle or by a key from the outside which lifts the handle 2 lever, or if desired this deadlock which engages the spring urged bolt to hold it in the full stroke position may be adapted to be released only by the insertion of the key.

The invention will be further described with reference to the accompanying drawings which illustrate several embodiments of the improved night latch and in which Figs. 1 and 2 are respectively horizontal and vertical part sectional views of one embodiment suitable for use in coniunction with a cylinder type lock even though the movement of the bolt from inside the door is elfected by reciprocating the handle or knob, Fig. 1 being taken on the line I-I of Fig. 2, and Fig. 2'being taken on the line 11-11 of Fig. 1, while Figs. 3, 4 and 5 show an alternative arrangement also suitable for use with a cylinder type lock, Fig. 3 being a horizontal central sectional view on the line III-I[I of Fig. 4, Fig. 4 a vertical sectional view on the line IV-IV of Fig. 3 and Fig. 5, a view of the keeper, movement of the bolt from inside the door being effected in this case by rotary movement of the handle or knob.

Referring now to the drawings in which like reference characters indicate like or equivalent parts, and turning first more specifically to Figs. 1 and 2, the latch case I is a rectangular pressing or stamping of the sheet metal adapted to be screwed to the inside face of the door represented at 2 and having a lip or flange 3 preferably rabbeted into the vertical edge of the door, 4 being a rectangular aperture in the end wall of the latch case I carrying the flange 3, through which aperture reciprocates the bolt or latch designated 5, the latter when projected into the keeper 10 as shown, securing the door.

6 represents a yoke shaped member of metal, Y

suitably bent up from mild steel plate, secured by screws 7 to a rearward shank portion 8 of the bolt 5 and 9 is a tension spring between an eye II on an arm 12 of a detent l3 pivotally carried at M by the end wall of the latch case I adjacent the aperture and a second eye 01' hook I5 at the rearward end of the member 6, the spring 9 normally tending to urge the bolt assembly 5 and 5 to the positions shown in full lines with the bolt fully projected or advanced into the keeper Ill. To unlock the door the bolt requires to be slidden against the tension of the spring 9 until its nose is clear of the keeper l5] and for this purpose projecting through the inwardly facing wall of the latch case I from the member 6 of the bolt assembly is a'pin I 8 carrying a knob I9, the wall of the latch case bein formed with an appropriate horizontal guide slot 20 in which the pin it rides, and this slot being formed with short traverse or locking notches 2| into which the pin 18 falls, preventing inadvertent movement of the bolt except when the knob i9 is deliberately lifted to bring the pin 18 into horizontal alignment with the slot. It will be appreciated that the pin I8 is mounted in the member' t' in such manner that itv can be moved vertically in relation thereto in order to be able to pass into the short traverse or locking notches 2|, thus preventing movement of the pawl 5.

' embodiment.

The detent 13 has a nose 25 bent upwardly into the space within the yoke shaped plate of the bolt assembly, such detent nose 25 riding unidirectionally in a counter-clockwise direction when viewed in Fig. 1 around a track which includes a spring leaf 25 of flattened 3 formation and a. U shaped notch 21 bothcarried by a plate 23 mounted inside the yoke. Clockwise torque is applied to the detent [3 by the spring 9 so that its nose is urged downwardly and on the bolt being retracted the nose 25 is first lifted by the inclination of its guide. leaf 2.6 and when it reaches. the end of such. leaf, the detent I3 is moved by its spring 8 so that itsnose 25 occupies the notch 2'! thus to hold the bolt 5 in the partially projected or snap lock position shown dotted in Fig. 1. A. guard pin 29 prevents the detent 13 being shot by its spring across the mouth of the notch 2 When the bolt 5 is held by the detent nose 25 engaging the notch. 21-, the door 2 can be slammed and, since the bevel I6 on the bolt engages the striker plate I! of the keeper l0, thebolt is forced inwardly against its spring to.- pass the striker plate and is then shot. to its full stroke position in, which the door is locked.

During this movement of the bolt the, nose 25 first jumps downwardly out. ofv notch 2! and then slides along the wall of the yoke 5 passing under the free lower end of the leaf guide 26 which is carried near its upper end and which thus also acts as a gate ensuring the unidirectional travel of the detent around its track and thus thealternate relationship of the half and full stroke positions of the bolt.

Owing to the half. stroke feature or intermediate position, the bolt 5 may have bevels such as 1-3 on both faces to suit right and left hand doors, or the nose portion of the bolt may be detachable and reversible.

30 represents a cylinder lock. on the outside of the door 2 connected by an operating shaft 3! to. a rocker 32 within the latch case I so that rotation of the appropriate key in the lock actuates the bolt 5 owing to the rocker 32 coming into contact with an abutment plate 33 on the bolt assembly and retracting it against the spring 9 which also operates the detent.

Referring now to the embodiment illustrated in Figs. 3 to 5, be generally designates the latch case, 2A the door, 3A a flange on the latch case having an aperture to take a countersunk screw passing into the end of the door, 4A the guide aperture and 5A the bolt which in this construction is formed within the latch case with a plate 35 recessed at 36 into the bolt head proper and the rear end of the bolt plate 35 being formed with upper and lower ears 3? either or both of which provide the movable anchorage for a retention spring 38,, the other end of which is connested to a stationary eye 39 on the end wall of the. latch case irom which the bolt-5A projects,

detent the U.

The inner wall of the cam track 45 is constituted by a shaped component 48 formed integrally with the plate 35 and providing the .notch 41, and a rocking gate component 49 pivoted at 50 on the plate component 35 of the bolt.

During retraction of" the bolt from its full stroke position by rotation of the key or the like, the pin 14 of the detent 43 rides around the up.- per part of the cam. track 45 in a counter-clockwise direction as viewed, in Fig. 4 and passes into the notch 41 to prevent the bolt. being projected by the spring 38 beyond its half stroke or snaplock position. Onthe next successive retraction of the bolt, e. g. by the door being slammed or by manipulation of the key or knob, the detent tail pin 44 then passes downwardly from the notch 4? along the bottom of the track 45 where it comes into abutment with the nose 5| of the. rocking gate 4!] raising the latter about its pivot 55 and passing through the gateway into the full stroke notch 45 so that the bolt, 5A is. permitted to be projected fully by the spring 38, the rocker l8 falling back into the position shown and ensuring that the. detent tail pin continues its unidirectional movement around the cam track 15 on the next retractionof the bolt. As is shown more clearly in Fig. 3 the detent 43 pivots about a journal 55 formed integrally with the latch case IA, the detent being welded to a bush 56 bearing on the latter.

5? is a plate which forms an automatic deadlock, said plate, which is constantly stressed by a spring 51a, being carried by a pin 58 and having a tine 59 which takes into a notch on the lower edge of the plate. component 35. of the bolt when the latter is projected to its full stroke position. This deadlock is adapted to be released by a lever arm 6| when the cylinder lock, is turned by the appropriate key, an arm 62 coming into abutment with the ear 3! on continued movement of the key or the knob to retract, the bolt 5 from its keeper IDA and allow the door to be opened.

It will be understood that the improved construction of. the two throw lock may be. adapted to be morticed into the door if desired, although since the bevelled end. of the bolt head is inthe full stroke position, well inside the keeper. the security of a mortice. lock is obtained without it being necessary to recess the look into the door. What I claim is: 1 1. A latch-type lock comprising a casing, 2 double throw bolt slidably mounted in said casing, a spring urging said bolt towards a full throw position, a labyrinth cam track carried by said bolt, a detent pivoted in said casing and having a tail riding in said cam track, a half throw notch in said track engaged by the tail to control the throw of theebolt, and a gate member pivotahy mounted on said bolthavingasurface. ccns'zi-v' tuting apart-of said cam track and ensuring imiv) claim 1 including an automatic deadlock preventing retraction of the bolt from its full stroke position by external pressure on the bolt.

HAROLD THORNE.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,286,344 Kenneweg Dec. 3. 1918 Number Number Name Date Boge Oct. 30, 1923 Niederdrenk May 31, 1938 FOREIGN PATENTS Country Date Great Britain July 21, 1936 Germany Dec. 20, 1939 

